Monitor time for statement to execute

Question

I have a procedure that issues an ALTER INDEX ... REBUILD statement. How can I determine the total time it takes for this statement to complete? I'm trying to compare the time it takes to rebuild an index with logging and without logging.
Thanks.

Answer 1

Hi steve,
when tuning SQL statements, you may wish to determine the steps that the optimizer will take to execute your query. To view the query path, your database should have PLAN_TABLE (check to see if this table already exists in your DB) else you must first create a table in your schema name PLAN_TABLE. The script used to create this table is called utlxplan.sql, and is usually stored in the /rdbms/admin subdirectory of the Oracle Software home directory.
After you have created the PLAN_TABLE table in your schema, you can use the explain plan command, which will generate the records in your PLAN_TABLE, tagged with statement_ID value you specify for the query you wish to have explained:
Example:
explain plan
set statement_ID = 'MYTEST'
for
select * from EMP
where EMP_NAME like 'M%';
In above case you will see two entries in the PLAN_TABLE table and the difference of the timestamp column b/w the first record and second record gives you the time taken to execute the above query.
Regards,
Murali Mohan